Systems and methods for cannabis CBD extraction

ABSTRACT

Systems and methods for extracting a compound of interest from plant material, such as acannabidiol (CBD) from cannabis, are provided. Particularly, the disclosed systems and methods utilize a crude oil to separate water, fats, and proteins prior to preparation of a CBD distillate. The systems and methods are operable with conventional solvents containing between about 5 wt % and about 8 wt % water.

FIELD OF THE INVENTION

This invention relates generally to systems and methods for extractingcannabidiol (CBD) from cannabis, and particularly to systems and methodsthat utilize a crude oil to separate water, fats, and proteins prior topreparation of a CBD distillate.

BACKGROUND OF THE INVENTION

At present, the most efficient methods for extracting cannabidiol (CBD)from cannabis plants are solvent extraction processes, in which thecannabis biomass is contacted with a liquid solvent. Ethanol is widelyconsidered the most effective solvent for such processes and is by farthe most commonly used. However, pure (99% purity or higher) ethanol isvery expensive and tightly regulated by many governments, and is thusextremely difficult to obtain in quantities sufficient forindustrial-scale applications (3,000 to 5,000 gallons). As a result,most skilled artisans use a mixture of ethanol and water, typicallycomprising 5% to 8% water, as the solvent in CBD solvent extractionprocesses.

The presence of water in CBD extraction solvents presents severaldrawbacks. Most significantly, when cannabis biomass is contacted withan aqueous solvent, fats and hydrophilic proteins in the cannabisbiomass are solubilized in the water. When the solvent is subsequentlyheated, as most separation processes require, the proteins in thesolvent solidify, thus fouling process equipment and requiring frequentshutdown and cleaning of the extraction system.

There is thus a need in the art for systems and methods for extractingCBD from cannabis that avoid or prevent fouling and clogging of theprocess equipment by proteins and other impurities present in thesolvent after extraction. It is further advantageous for such systemsand methods to be compatible with currently known, inexpensive, and/orwidely available solvents, e.g. ethanol/water mixtures.

SUMMARY OF THE INVENTION

It is one aspect of the present invention to provide a method forseparating a first organic substance from a second organic substance inan aqueous solution or suspension, comprising (a) providing the aqueoussolution or suspension, the aqueous solution or suspension comprisingthe first and second organic substances; (b) forming a first phase and asecond phase from the aqueous solution or suspension by at least one of(i) contacting the aqueous solution or suspension with at least one of aliquid separating agent and a solid separating agent, and (ii) at leastone of centrifugation, filtration, and sedimentation of the aqueoussolution or suspension; and (c) removing one of the first phase and thesecond phase to a vessel, wherein the first organic substance comprisesat least one of a cannabinoid and a terpene, wherein the second organicsubstance comprises at least one of a protein and a lipid, wherein thefirst phase comprises at least most of the first organic substancepresent in the aqueous solution or suspension, wherein the second phasecomprises at least most of the second organic substance present in theaqueous solution or suspension, and wherein the first and second phasesare substantially immiscible.

In embodiments, the first organic substance may comprise a cannabinoid.The cannabinoid may, but need not, be cannabidiol.

In embodiments, the aqueous solution or suspension may originate from anethanol extraction process for extraction of the first organic substancefrom cannabis plant material. The method may, but need not, furthercomprise obtaining a solid fraction of the second phase by at least oneof drying the second phase and filtering the second phase; and recyclingthe solid fraction of the second phase to the ethanol extractionprocess.

In embodiments, the method may further comprise providing the firstphase to a distillation process for producing a distillate of the firstorganic substance.

In embodiments, the first phase may comprise at least about 75% of thefirst organic substance present in the aqueous solution or suspension.

In embodiments, at least one step may be carried out at a temperature ofno more than about 75° C.

It is another aspect of the present invention to provide a method forpreparing a purified cannabis extract, comprising (a) contactingcannabis plant material with a liquid mixture of ethanol and water toform a raw extract comprising ethanol, water, at least one cannabinoidor terpene, and at least one protein or lipid; (b) recovering at leastmost of the ethanol from the raw extract to form a crude cannabis oil;(c) forming a first phase and a second phase from the crude cannabis oilby at least one of (i) contacting the aqueous solution or suspensionwith at least one of a liquid separating agent and a solid separatingagent, and (ii) at least one of centrifugation, filtration, andsedimentation of the aqueous solution or suspension; (d) removing one ofthe first phase and the second phase to a vessel; and (e) distilling thefirst phase to form the purified cannabis extract, wherein the firstphase comprises at least most of the at least one cannabinoid or terpenepresent in the crude cannabis oil, wherein the second phase comprises atleast most of the at least one protein or lipid present in the crudecannabis oil, and wherein the first and second phases are substantiallyimmiscible.

In embodiments, the at least one cannabinoid or terpene may comprisecannabidiol.

In embodiments, the method may further comprise obtaining a solidfraction of the second phase by at least one of drying the second phaseand filtering the second phase; and recycling the solid fraction of thesecond phase to step (b) as part of the raw extract or to step (c) aspart of the crude cannabis oil.

In embodiments, the first phase may comprise at least about 75% of thecannabinoid or terpene present in the crude cannabis oil.

In embodiments, at least one of steps (a), (b), (c), and (d) may becarried out at a temperature of no more than about 75° C.

In embodiments, the purified cannabis extract may be substantially freeof proteins and lipids.

In embodiments, the purified cannabis extract may comprise at leastabout 70 wt % cannabinoids and terpenes. The purified cannabis extractmay, but need not, comprise at least about 70 wt % cannabidiol.

It is another aspect of the present invention to provide a liquidcomposition, comprising at least about 70 wt % cannabinoids and terpenesand being substantially free of proteins and lipids.

In embodiments, the liquid composition may comprise at least about 70 wt% cannabidiol. The liquid composition may, but need not, besubstantially free of cannabidiolic acid.

In embodiments, the liquid composition may be produced by a methodcomprising (a) providing the aqueous solution or suspension, the aqueoussolution or suspension comprising the first and second organicsubstances; (b) forming a first phase and a second phase from theaqueous solution or suspension by at least one of (i) contacting theaqueous solution or suspension with at least one of a liquid separatingagent and a solid separating agent, and (ii) at least one ofcentrifugation, filtration, and sedimentation of the aqueous solution orsuspension; (c) removing one of the first phase and the second phase toa vessel; and (d) distilling the first phase, wherein the first organicsubstance comprises at least one of a cannabinoid and a terpene, whereinthe second organic substance comprises at least one of a protein and alipid, wherein the first phase comprises substantially all of the firstorganic substance present in the aqueous solution or suspension and issubstantially free of the second organic substance, wherein the secondphase comprises substantially all of the second organic substancepresent in the aqueous solution or suspension and is substantially freeof the first organic substance, and wherein the first and second phasesare substantially immiscible.

In embodiments, the liquid composition may be produced by a methodcomprising (a) contacting cannabis plant material with a liquid mixtureof ethanol and water to form a raw extract comprising ethanol, water, atleast one cannabinoid or terpene, and at least one protein or lipid; (b)recovering at least most of the ethanol from the raw extract to form acrude cannabis oil; (c) forming a first phase and a second phase fromthe crude cannabis oil by at least one of (i) contacting the aqueoussolution or suspension with at least one of a liquid separating agentand a solid separating agent, and (ii) at least one of centrifugation,filtration, and sedimentation of the aqueous solution or suspension; (d)removing one of the first phase and the second phase to a vessel; and(e) distilling the first phase to form the purified cannabis extract,wherein the first phase comprises at least most of the at least onecannabinoid or terpene present in the crude cannabis oil, wherein thesecond phase comprises at least most of the at least one protein orlipid present in the crude cannabis oil, and wherein the first andsecond phases are substantially immiscible.

It is another aspect of the present invention to provide a system forpreparing a purified plant extract, comprising a centrifugal separationunit, comprising at least one centrifugal separator, configured toreceive plant material and a liquid solvent comprising ethanol, mix theplant material and the liquid solvent to form a slurry, and centrifugethe slurry in the centrifugal separator to separate the slurry into asolid residue and a raw extract, wherein the raw extract comprises atleast one compound of interest and at least most of the liquid solvent;a filtration unit, comprising a filter assembly, configured to filterthe raw extract to remove entrained solid plant material from the rawextract; a concentration unit, comprising an evaporator configured toreceive the raw extract and heat the raw extract to remove at least mostof the solvent therefrom by evaporation to thereby form a concentratedextract; a settling unit, comprising at least one settling vessel,configured to receive the concentrated extract and cause sedimentationof at least one impurity therefrom; a decarboxylation and degassingunit, comprising an atmosphere heating vessel and a vacuum heatingvessel, wherein the atmosphere heating vessel is configured to receivethe concentrated extract from the settling unit and heat theconcentrated extract under approximately ambient or atmospheric pressureto decarboxylate at least a portion of the concentrated oil to form adecarboxylated oil, wherein the vacuum heating vessel is configured toreceive the decarboxylated oil from the atmosphere heating vessel andheat the decarboxylated oil under sub-atmospheric pressure to form awinterized oil; and a short-path distillation unit, comprising at leastone short-path distillation apparatus configured to receive thewinterized oil from the decarboxylation and degassing unit and distillthe winterized oil to form the purified plant extract.

In embodiments, the plant material may be a cannabis plant material.

In embodiments, the at least one compound of interest may comprise atleast one cannabinoid or terpene. The at least one compound of interestmay, but need not, comprise cannabidiol.

In embodiments, a content of the at least one compound of interest inthe purified plant extract may be at least about 70% by weight.

In embodiments, the liquid solvent may consist essentially of (i)between about 92 and about 95 wt % ethanol and (ii) water.

In embodiments, the at least one impurity may comprise at least oneprotein or lipid.

In embodiments, the system may further comprise a rectification unit,configured to receive evaporated solvent from the concentration unit andrecover the solvent for recycle to at least one other unit of thesystem.

It is another aspect of the present invention to provide a method forpreparing a purified plant extract, comprising (a) contacting plantmaterial with a liquid solvent containing ethanol to form a slurry; (b)centrifuging the slurry to form a raw extract comprising at least onecompound of interest and at least most of the liquid solvent; (c)filtering the raw extract to remove entrained solid plant material fromthe raw extract; (d) concentrating the raw extract by heating the rawextract to remove at least most of the solvent therefrom by evaporationto thereby form a concentrated extract; (e) precipitating a sedimentcomprising at least one impurity from the concentrated extract; (f)decarboxylating the concentrated extract by heating the concentratedextract under approximately ambient or atmospheric pressure to form adecarboxylated oil; (g) heating the decarboxylated oil undersub-atmospheric pressure to form a winterized oil; and (h) distillingthe winterized oil by short-path distillation to form the purified plantextract.

In embodiments, the plant material may be a cannabis plant material.

In embodiments, the at least one compound of interest may comprise atleast one cannabinoid or terpene. The at least one compound of interestmay, but need not, comprise cannabidiol.

In embodiments, a content of the at least one compound of interest inthe purified plant extract may be at least about 70% by weight.

In embodiments, the liquid solvent may consist essentially of (i)between about 92 and about 95 wt % ethanol and (ii) water.

In embodiments, the at least one impurity may comprise at least oneprotein or lipid.

In embodiments, the method may further comprise rectifying the solventevaporated in step (d) for recycle to at least one of steps (a), (b),and (c).

For purposes of further disclosure and to comply with applicable writtendescription and enablement requirements, the following referencesgenerally relate to systems and methods for extracting a compound orcompounds of interest from plant material and/or separating organiccompounds and impurities from an aqueous solution or suspension, and arehereby incorporated by reference in their entireties:

U.S. Pat. No. 9,937,218, entitled “Systems and methods for cannabinoidand terpene extraction and purification,” issued 10 Apr. 2018 to Towle.

U.S. Pat. No. 9,994,464, entitled “Method and devices for de-emulsifyingand complexing organic compounds in emulsions,” issued 12 Jun. 2018 toDietz.

The phrases “at least one”, “one or more”, and “and/or” are open-endedexpressions that are both conjunctive and disjunctive in operation. Forexample, each of the expressions “at least one of A, B and C”, “at leastone of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B,or C” and “A, B, and/or C” means A alone, B alone, C alone, A and Btogether, A and C together, B and C together, or A, B and C together.When each one of A, B, and C in the above expressions refers to anelement, such as X, Y, and Z, or class of elements, such as X₁-X_(n),Y₁-Y_(m), and Z₁-Z_(o), the phrase is intended to refer to a singleelement selected from X, Y, and Z, a combination of elements selectedfrom the same class (e.g., X₁ and X₂) as well as a combination ofelements selected from two or more classes (e.g., Y₁ and Z_(o)).

The term “a” or “an” entity refers to one or more of that entity. Assuch, the terms “a” (or “an”), “one or more” and “at least one” can beused interchangeably herein. It is also to be noted that the terms“comprising”, “including”, and “having” can be used interchangeably.

It should be understood that every maximum numerical limitation giventhroughout this disclosure is deemed to include each and every lowernumerical limitation as an alternative, as if such lower numericallimitations were expressly written herein. Every minimum numericallimitation given throughout this disclosure is deemed to include eachand every higher numerical limitation as an alternative, as if suchhigher numerical limitations were expressly written herein. Everynumerical range given throughout this disclosure is deemed to includeeach and every narrower numerical range that falls within such broadernumerical range, as if such narrower numerical ranges were all expresslywritten herein.

The preceding is a simplified summary of the disclosure to provide anunderstanding of some aspects of the disclosure. This summary is neitheran extensive nor exhaustive overview of the disclosure and its variousaspects, embodiments, and configurations. It is intended neither toidentify key or critical elements of the disclosure nor to delineate thescope of the disclosure but to present selected concepts of thedisclosure in a simplified form as an introduction to the more detaileddescription presented below. As will be appreciated, other aspects,embodiments, and configurations of the disclosure are possibleutilizing, alone or in combination, one or more of the features setforth above or described in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a process flow diagram of a method for separating a firstorganic substance from a second organic substance in an aqueous solutionor suspension, according to embodiments of the present invention.

FIG. 2 is a process flow diagram of a method for preparing a purifiedcannabis extract, according to embodiments of the present invention.

FIG. 3 is an illustration of a centrifugal separation unit of a systemfor preparing a purified cannabis extract, according to embodiments ofthe present invention.

FIG. 4 is an illustration of a filter unit of a system for preparing apurified cannabis extract, according to embodiments of the presentinvention.

FIG. 5 is an illustration of a concentration unit of a system forpreparing a purified cannabis extract, according to embodiments of thepresent invention.

FIG. 6 is an illustration of a rectification unit of a system forpreparing a purified cannabis extract, according to embodiments of thepresent invention.

FIG. 7 is an illustration of a static separation unit of a system forpreparing a purified cannabis extract, according to embodiments of thepresent invention.

FIG. 8 is an illustration of a decarboxylation and degassing unit of asystem for preparing a purified cannabis extract, according toembodiments of the present invention.

FIG. 9 is an illustration of a short-path distillation unit of a systemfor preparing a purified cannabis extract, according to embodiments ofthe present invention.

FIG. 10 is a process flow diagram of the comprehensive method forproducing cannabis extract incorporating steps of contacting withsolvent, centrifuging, filtering, concentrating, settling,decarboxylating, winterizing and short-path distillation.

The accompanying drawings are incorporated into and form a part of thespecification to illustrate several examples of the present disclosure.The drawings are not to be construed as limiting the disclosure to onlythe illustrated and described examples.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, unless otherwise specified, the term “cannabis” refersto any plant in the genus Cannabis.

As used herein, unless otherwise specified, the term “hemp” refers tocannabis plant material containing no more than about 0.3%tetrahydrocannabinol by weight.

As used herein, unless otherwise specified, the term “plant material”refers to whole plants and/or parts of plants that contain one or morecompounds to be extracted, including but not limited to aerial parts,leaves, stems, flowering heads, fruits, and/or roots. “Plant material”may be freshly harvested plants or parts of plants, plants or parts ofplants that have been subjected to one or more pre-treatment steps (e.g.drying, removal of debris, etc.), and/or plants or parts of plants thathave been frozen or pelletized.

Before any embodiments of the disclosure are explained in detail, it isto be understood that the disclosure is not limited in its applicationto the details of construction and the arrangement of components setforth in the following description or illustrated in the followingdrawings. The disclosure is capable of other embodiments and of beingpracticed or of being carried out in various ways. Also, it is to beunderstood that the phraseology and terminology used herein is for thepurpose of description and should not be regarded as limiting. The useof “including,” “comprising,” or “having” and variations thereof hereinis meant to encompass the items listed thereafter and equivalentsthereof as well as additional items. Further, the present disclosure mayuse examples to illustrate one or more aspects thereof. Unlessexplicitly stated otherwise, the use or listing of one or more examples(which may be denoted by “for example,” “by way of example,” “e.g.,”“such as,” or similar language) is not intended to and does not limitthe scope of the present disclosure.

Although the following description generally refers to embodiments inwhich the methods and systems of the invention are employed to extract,e.g., cannabinoids from, e.g., cannabis, it is to be expresslyunderstood that the present invention may be suitably applied to anyplant or other biomass material to extract any compound that may beobtained by distillation. By way of non-limiting example, the presentinvention may be employed to extract essential oils or other volatilecompounds from spices, fruits, flowers, or any other suitable plantmaterial, as such embodiments are within the scope of the presentinvention.

One advantage of methods and systems of the present invention is thatcannabis extracts produced by the present invention may contain a blendof cannabinoids in approximately the same proportion as are present inthe raw cannabis plant material. In other words, little or nofractionation of cannabinoids may be observed so a “Full Spectrum”product is produced that reflects the cannabinoid profile of thefeedstock.

Crude oils produced from conventional ethanol extraction processesgenerally comprise at least some lipids and proteins dissolved in water.Additionally or alternatively, such crude oils may comprise carboxylicacids, phospholipids, glycolipids, glyceroglycolipids, phenols, sterols,squalene, plant dyes, such as chlorophylls and carotenes, sinapines,peptides, proteins, carbohydrates, lipoproteins, waxes and/or fattyalcohols. Thereby, the carboxylic acids, phospholipids, glycolipids,glyceroglycolipids, phenols, sterols, squalene, plant dyes, such aschlorophylls and carotenes, sinapines, peptides, proteins,carbohydrates, lipoproteins, flavoring agents, waxes and/or fattyalcohols may be present individually or as a mixture in the aqueoussolutions or suspensions, e.g., for example, as a mixture of peptides,sterols, and carbohydrates or a mixture of glycolipids andphospholipids. Aqueous solutions and suspensions suitable for refinementaccording to the present invention may also contain phospholipids,glycolipids, glyceroglycolipids, phenols, sterols, squalene, flavorings,vegetable dyes, such as chlorophylls and carotenoids, and/or sinapinesapart from carboxylic acids.

According to the present invention, proteins, lipids, and similarorganic substances that may be considered impurities or otherwiseundesirable may be separated from cannabinoids, terpenes, and othercompounds of interest by separating crude aqueous solutions orsuspensions, e.g. crude extracts or oils of cannabis, into two distinctphases, one phase being relatively rich in the cannabinoids/terpenes andrelatively poor in the proteins, lipids, etc., and the other phase beingrelatively poor in the cannabinoids/terpenes and relatively rich in theproteins, lipids, etc. This phase separation may be accomplished by anyone or more of several means. By way of first non-limiting example,phase separation may be achieved by chemical means, e.g. by contactingthe aqueous solution or suspension with a liquid or solid separatingagent. By way of second non-limiting example, phase separation may beachieved by physical means, e.g. by centrifugation, filtration, and/orsedimentation of the aqueous solution or suspension.

Chemical separating agents in any form, e.g. solids, powders, aqueousdispersions of solids, etc., can be added to crude extracts and oils asdisclosed in the methods described herein. In embodiments, the additionmay be carried out by mixing, and/or at a maximum temperature of about75° C., and/or with a laminar agitator.

Aqueous extraction mixtures suitable for separation according to thepresent invention may contain, besides the above-mentioned proteins,lipids, and carboxylic acids, phospholipids, glycolipids,glyceroglycolipids, phenols, sterols, squalenes, and/or vegetable dyes,such as chlorophylls and carotenes. These and other similar organicsubstances may likewise be separated from cannabinoids, terpenes, and/orother compounds of interest according to the present invention.

Methods of the present invention may or may not include adjusting the pHof the crude plant extract or oil or other aqueous solution orsuspension of interest. In some embodiments, the pH of one or bothphases after separation may be approximately equal to that of theinitial aqueous solution, i.e. before separation. Methods of the presentinvention may thus be useful to treat acidic solutions or suspensions,basic solutions or suspensions, and/or neutral solutions or suspensions.

The present invention may be useful to separate proteins and/or lipidsfrom other compounds of interest regardless of the physical nature ofthe initial aqueous suspension or solution from which the compounds areto be separated. By way of first non-limiting example, the aqueoussolution or suspension may be a true solution, i.e. the protein(s)and/or lipid(s) may be dissolved throughout an aqueous solvent. By wayof second non-limiting example, the aqueous solution or suspension maybe a colloid, i.e. the protein(s) and/or lipid(s) may be dispersedthroughout an aqueous liquid dispersion medium as solid or liquidparticles that are too small for sedimentation, or sufficiently smallthat the sedimentation time is impractically long. By way of thirdnon-limiting example, the aqueous solution or suspension may be anon-colloidal suspension, i.e. the protein(s) and/or lipids may bedispersed throughout an aqueous liquid dispersion medium as macroscopicsolid or liquid particles.

Particularly, the inventive process is suitable for aqueous solutions orsuspensions that originate from solvent extraction processes forextracting one or more compounds of interest from solid material, andespecially from ethanol extraction processes for extracting one or morecompounds of interest from plant material, e.g. cannabis plant material.As described throughout this disclosure, crude extracts resulting fromsuch processes may contain, in addition to a compound of interest (e.g.a cannabinoid or terpene), water and water-soluble proteins and lipidsextracted from the plant material. Typically, such extracts must bedistilled to provide a purified extract, but heating of the crudeextract may result in solidification or sedimentation of the proteinsand/or lipids, which may foul process equipment. By separating a phasecontaining organic impurities such as proteins and lipids from a phasecontaining the compound of interest, the present invention greatlymitigates the need to unclog or clean process equipment, resulting ingreater process uptime and reduced cost.

In embodiments, the methods of the present invention result in theformation of an aqueous phase comprising protein(s) and/or lipid(s) thatcan be re-processed or further processed to separate residual compoundsof interest, e.g. cannabinoids or terpenes, remaining in such phase.Particularly, the protein/lipid phase resulting from separationsaccording to the present invention can be filtered and/or dried toproduce a solid fraction, which may then be subjected to an extractionprocess, e.g. recycled to an earlier solvent extraction process. In thisway, methods of the present invention are suitable not only to avoidfouling of process equipment in solvent extraction/distillationprocesses for purification of compounds of interest, but also to improvethe overall recovery of the compounds of interest in such processes.Such filtration and/or drying may, in some embodiments, also result in arelatively high-purity liquid fraction of water, which may likewise beuseful in other processes and/or steps.

One advantage of the present invention relative to conventional methodsis that both the compound(s) of interest, e.g. cannabinoids andterpenes, and the protein(s) and lipid(s) to be separated from thecompounds of interest may be obtained without significant physical orchemical degradation or decomposition. More specifically, embodiments ofthe methods of the present invention do not require exposure ofsensitive organic compounds to extreme temperatures or pressures, or tostrong acids, bases, or other chemicals that may degrade, causehydrolysis of, or otherwise damage the compound(s) of interest,protein(s), or lipid(s); in fact, it may in many embodiments bepreferable to carry out the methods of the present invention at moderatetemperatures (e.g. between about 0° C. and about 100° C., between about15° C. and 75° C., between about 20° C. and about 50° C., or betweenabout 25° C. and about 35° C., or in some embodiments no more than about75° C.). As a result, either phase, or both phases, can be furtherprocessed to yield a safe and high-purity product, e.g. a cannabisdistillate comprising at least about 70% cannabinoids and/or terpenes byweight. Proteins and lipids separated from the aqueous solution orsuspension may likewise be in a chemically and physically intact and/orneutral form suitable for further use, e.g. in foods, cosmetic products,pharmaceuticals, flavoring agents, etc.

Neutral lipids may present particular separation challenges because theytypically cannot be separated from aqueous solutions or suspensions byphysical means such as centrifugation. By the practice of the presentinvention, separation of the neutral lipids present in aqueous solutionsand suspensions can be obtained, e.g., by increasing a separationtemperature and inducing aggregation of the neutral lipids. In this way,the methods of the present invention enable the separation of neutralfats from aqueous solutions and suspensions, either from compounds ofinterest or from proteins and other lipids.

Embodiments of the present invention may advantageously result in theformation of a phase containing a relatively high proportion of waterand a phase containing a relatively low proportion of water.Particularly, in embodiments, the methods of the present invention mayproduce a water-poor phase that is rich in the compound(s) of interest,e.g. cannabinoids and terpenes, and a water-rich phase that is rich inimpurities, e.g. protein(s) and lipids. The water-poor phase can then befurther purified, e.g. by distillation or other temperature- orpressure-intensive methods, without causing fouling or clogging ofprocess equipment, while the water-rich phase can be recycled, purged,or further purified by any of several well-known means, such as the useof decanters, separators, filter technology, vacuum drying, inert gasdrying, heating, etc. to separate organic aggregates, e.g. proteins andlipids. In addition, the shelf life of the compound(s) of interest inthe water-poor phase may be extended, due to the avoidance of physicalcontact with impurities and water for an extended period, and theproteins and lipids may likewise be suitable for later use in otherproducts or processes.

Embodiments of the present invention allow more efficient and effectiveseparation of compounds of interest, e.g. cannabinoids and terpenes,from protein and lipid impurities than conventional separation methods.By way of first non-limiting example, methods of the present inventionmay allow for formation of a cannabinoid- and/or terpene-rich phase thatcomprises at least about 50 wt %, at least about 55 wt %, at least about60 wt %, at least about 65 wt %, at least about 70 wt %, at least about75 wt %, at least about 80 wt %, at least about 85 wt %, at least about90 wt %, at least about 95 wt %, at least about 96 wt %, at least about97 wt %, at least about 98 wt %, or at least about 99 wt % of thecannabinoids and/or terpenes present in the input aqueous solution orsuspension. By way of second non-limiting example, methods of thepresent invention may allow for formation of a protein- and/orlipid-rich phase that comprises at least about 50 wt %, at least about55 wt %, at least about 60 wt %, at least about 65 wt %, at least about70 wt %, at least about 75 wt %, at least about 80 wt %, at least about85 wt %, at least about 90 wt %, at least about 95 wt %, at least about96 wt %, at least about 97 wt %, at least about 98 wt %, or at leastabout 99 wt % of the proteins and/or lipids present in the input aqueoussolution or suspension. By way of third non-limiting example, methods ofthe present invention may allow for formation of a protein- and/orlipid-poor phase that comprises no more than about 50 wt %, no more thanabout 45 wt %, no more than about 40 wt %, no more than about 35 wt %,no more than about 30 wt %, no more than about 25 wt %, no more thanabout 20 wt %, no more than about 15 wt %, no more than about 10 wt %,no more than about 5 wt %, no more than about 4 wt %, no more than about3 wt %, no more than about 2 wt %, or no more than about 1 wt % of theproteins and/or lipids present in the input aqueous solution orsuspension. By way of fourth non-limiting example, methods of thepresent invention may allow for formation of a cannabinoid- and/orterpene-poor phase that comprises no more than about 50 wt %, no morethan about 45 wt %, no more than about 40 wt %, no more than about 35 wt%, no more than about 30 wt %, no more than about 25 wt %, no more thanabout 20 wt %, no more than about 15 wt %, no more than about 10 wt %,no more than about 5 wt %, no more than about 4 wt %, no more than about3 wt %, no more than about 2 wt %, or no more than about 1 wt % of thecannabinoids and/or terpenes present in the input aqueous solution orsuspension.

In some embodiments, separation of proteins and/or lipids from compoundsof interest may be effectuated by initiating aggregation and subsequentsedimentation of proteins and/or lipids from the aqueous solutions orsuspension, thus leaving behind a phase containing the compound ofinterest and having a diminished content of proteins and/or lipids. Inthese and other embodiments, separation of proteins and/or lipids fromcompounds of interest may be effectuated by initiating separation of thesolution into a water-poor or hydrophobic phase, which preferentiallyincludes oily, hydrophobic, or poorly water-soluble contents of theaqueous solution or suspension (e.g. cannabinoids, terpenes, etc.), anda water-rich or hydrophilic phase, which preferentially includes waterand hydrophilic, amphiphilic, or highly water-soluble contents of theaqueous solution or suspension (e.g. proteins, lipids, etc.). In someembodiments, it may be possible to decant or otherwise separate thewater of the protein- or lipid-rich phase from the proteins and lipids,e.g. when the aqueous solution or suspension is separated into twoliquid phases and the proteins and lipids subsequently aggregate andprecipitate out of a water-rich liquid phase. Alternatively, solid orsemi-solid aggregates of proteins, lipids, and/or other impurities may,standing alone, constitute all or a majority of the mass or volume of aphase, in which case it may be possible to separate the entire liquidcontents of the reactor or vessel in which separation is being carriedout, e.g. by means of a sieve or filter. In any of these embodiments,either phase may be washed or further processed to improve fractionationstill further.

Referring now to FIG. 1, a method 100 for separating a first organicsubstance from a second organic substance in an aqueous solution orsuspension is illustrated, according to embodiments of the presentinvention. In the embodiment illustrated in FIG. 1, the method 100comprises a providing step 110, a forming step 120, and a removing step130.

In the providing step 110 of the method 100, an aqueous solution orsuspension, comprising a first organic substance and a second organicsubstance, is provided. In embodiments, the first organic substancegenerally includes at least one cannabinoid, at least one terpene, or acombination or mixture thereof, and the second organic substancegenerally includes at least one protein, at least one lipid, or acombination or mixture thereof, but it is to be expressly understoodthat various other organic substances may be suitable, as describedthroughout this disclosure. In some preferred embodiments, the firstorganic substance may comprise cannabidiol (CBD), and the second organicsubstance may comprise a combination or mixture of at least partiallywater-soluble, water-miscible, and/or hydrophilic protein(s) and/orlipids, particularly protein(s) and/or lipid(s) susceptible tosolidification (and thus fouling or clogging of process equipment) uponheating. In many embodiments, the aqueous solution may be a crudecannabis extract, and particularly the product of an ethanol extractionprocess for extraction of a compound of interest (i.e. the first organicsubstance or a component thereof) from cannabis plant material.

In the forming step 120 of the method 100, the aqueous solution orsuspension is separated into a first phase and a second phase by anysuitable means. By way of first non-limiting example, the first andsecond phases may be formed by contacting the aqueous solution orsuspension with a solid separating agent and/or a liquid separatingagent; in embodiments, a liquid separating agent may be a liquid (e.g.aqueous) solution or dispersion of a solid separating agent (e.g. acopper salt, a calcium salt, a sodium salt, a magnesium salt, silica,etc.). By way of second non-limiting example, the first and secondphases may be formed by centrifuging the aqueous solution or suspension.By way of a third non-limiting example, the first and second phases maybe formed by filtering the aqueous solution or suspension. By way of afourth non-limiting example, the first and second phases may be formedby causing or triggering sedimentation of solid particles (e.g.comprising protein(s) and/or lipids) from the aqueous solution orsuspension. Generally, the first phase resulting from forming step 120is a first substance-rich phase, e.g. a cannabinoid- and/or terpene-richphase (e.g. comprising at least most, and in embodiments at least 75%,of cannabinoids and/or terpenes in the aqueous solution or suspension),and the second phase resulting from forming step 120 is a protein-and/or lipid-rich phase (e.g. comprising at least most of proteinsand/or lipids in the aqueous solution or suspension). Typically, thefirst and second phases may be substantially immiscible to facilitateremoving step 130.

In the removing step 130 of the method 100, one of the first and secondphases formed in forming step 120 is removed to a vessel separate fromthat in which forming step 120 is carried out. By way of firstnon-limiting example, the first phase may be skimmed or otherwiseremoved from a surface of the second phase where the first and secondphases are liquids and the first phase is less dense than the secondphase. By way of second non-limiting example, the second phase may befiltered or precipitated from the first phase where the first phase isliquid and the second phase is solid or mostly solid.

The method 100 may optionally include any one or more additional stepsnot illustrated in FIG. 1. By way of first non-limiting example, thesecond phase (i.e. the protein- and/or lipid-rich phase) can be filteredand/or dried, and the second phase (and/or a solid fraction thereof) canbe recycled to an ethanol extraction process. By way of secondnon-limiting example, the first phase can be provided to a distillationprocess for producing a distillate or purified extract, e.g. a purifiedcannabinoid extract.

In many embodiments, it may be preferable for the steps of the method100 to be carried out at approximately ambient temperatures, or at onlyslightly elevated temperatures. Particularly, it may be preferable toensure that the steps of the method 100 are carried out at temperaturesbelow those at which proteins and/or lipids of the aqueous solution orsuspension may solidify, e.g. no more than about 75° C.

Referring now to FIG. 2, a method for preparing a purified plant extractis illustrated, according to embodiments of the present invention. Inthe embodiment illustrated in FIG. 2, the method 200 comprises acontacting step 210, a recovering step 220, a forming step 230, aremoving step 240, and a distilling step 250.

In the contacting step 210 of the method 200, plant material issubjected to a solvent extraction process, and in particular embodimentsan ethanol extraction process, by being contacted with a liquid solvent(e.g. a mixture of ethanol and water). As a result of contacting step210, a raw extract is produced; the raw extract typically comprises thesolvent, a compound or compounds of interest (e.g. cannabinoids and/orterpenes, including but not limited to cannabidiol), and proteins and/orlipids soluble in the solvent or a component thereof.

In the recovering step 220 of the method 200, the solvent or a portionthereof (e.g. ethanol) is removed from the raw extract and optionallyrecycled to contacting step 210. Removal and recovery of at least aportion of the solvent generally improves the efficiency of subsequentprocessing steps and results in a purer finished extract.

In the forming step 230 of the method 200, the crude oil is separatedinto a first phase and a second phase by any suitable means. By way offirst non-limiting example, the first and second phases may be formed bycontacting the crude oil with a solid separating agent and/or a liquidseparating agent; in embodiments, a liquid separating agent may be aliquid (e.g. aqueous) solution or dispersion of a solid separating agent(e.g. a copper salt, a calcium salt, a sodium salt, a magnesium salt,silica, etc.). By way of second non-limiting example, the first andsecond phases may be formed by centrifuging the crude oil. By way ofthird non-limiting example, the first and second phases may be formed byfiltering the crude oil. By way of fourth non-limiting example, thefirst and second phases may be formed by causing or triggeringsedimentation of solid particles (e.g. comprising protein(s) and/orlipids) from the crude oil. Generally, the first phase resulting fromforming step 230 is a first substance-rich phase, e.g. a cannabinoid-and/or terpene-rich phase (e.g. comprising at least most, and inembodiments at least 75%, of cannabinoids and/or terpenes in the aqueoussolution or suspension, and having a low proportion of proteins and/orlipids), and the second phase resulting from forming step 230 is aprotein- and/or lipid-rich phase (e.g. comprising at least most ofproteins and/or lipids in the aqueous solution or suspension, and havinga low proportion of substances of interest such as cannabinoids and/orterpenes). Typically, the first and second phases may be substantiallyimmiscible to facilitate removing step 240.

In the removing step 240 of the method 200, one of the first and secondphases formed in forming step 230 is removed to a vessel separate fromthat in which forming step 230 is carried out. By way of firstnon-limiting example, the first phase may be skimmed or otherwiseremoved from a surface of the second phase where the first and secondphases are liquids and the first phase is less dense than the secondphase. By way of second non-limiting example, the second phase may befiltered or precipitated from the first phase where the first phase isliquid and the second phase is solid or mostly solid.

In the distilling step 250 of the method 200, the first phase, i.e. thephase containing the compound or compounds of interest (e.g.cannabinoids and/or terpenes), is distilled to further purify the firstphase and produce a purified extract.

The method 200 may optionally include any one or more additional stepsnot illustrated in FIG. 2. By way of non-limiting example, the secondphase (i.e. the protein- and/or lipid-rich phase) can be filtered and/ordried, and the second phase (and/or a solid fraction thereof) can berecycled to recovering step 220 and/or forming step 230.

In many embodiments, it may be preferable for at least one of, and insome embodiments all of, the contacting step 210, the recovering step220, the forming step 230, and the removing step 240 to be carried outat approximately ambient temperatures, or at only slightly elevatedtemperatures. Particularly, it may be preferable to ensure that at leastone of these steps of the method 200 is carried out at temperaturesbelow those at which proteins and/or lipids of the aqueous solution orsuspension may solidify, e.g. no more than about 75° C.

The method 200 may be suitable to obtain a cannabis plant extract havinga high proportion of cannabinoids, and in particular a high proportionof cannabidiol. Typically, the cannabinoid content of the purifiedextract may be at least about 70 wt %, and in some embodiments up toabout 80 wt %. The purified extract may be substantially free ofproteins and/or lipids, or may have a significantly lower content ofproteins and/or lipids relative to cannabis plant extracts obtained byconventional methods.

Referring now to FIG. 3, a centrifugal separation unit 300 of a systemfor preparing a purified cannabis extract, according to embodiments ofthe present invention, comprises an alcohol tank 301, an alcohol pump302, an optional refrigerator 303, and at least one centrifugalseparator 304 (in this case two centrifugal separators 304 a,b). Asillustrated in FIG. 3, ethanol is injected by the alcohol pump 302 fromthe alcohol tank 301 into either the optional refrigerator 303, thecentrifugal separator(s) 304, or both; most typically, at least aportion of ethanol used by the system will be cooled in the refrigerator303 prior to being injected into the centrifugal separator(s) 304. Theethanol is injected from the alcohol tank 301 and/or the refrigerator303 into the centrifugal separator(s) 304. Before, after, and/orsimultaneously with injection of the ethanol into the centrifugalseparator(s) 304, raw cannabis plant material is fed to the centrifugalseparator(s) 304 via a hopper (not illustrated); most typically, a massratio of the solvent to the raw cannabis plant material in thecentrifugal separator(s) 304 is about 5:1, but any suitable ratio may beused. The ethanol and cannabis plant material are fully mixed, mosttypically for between about 20 and about 40 minutes, to form a slurry,which is then centrifuged in the centrifugal separator(s) 304 toseparate the slurry into a solid residue and a crude oil. It is to beexpressly understood that one or more of the centrifugal separator(s)304 may consist of a single mixing/centrifuging vessel, whereby theethanol and cannabis plant material are slurried and subsequentlycentrifuged in the single mixing/centrifuging vessel, and/or one or moreof the centrifugal separator(s) 304 may consist of multiple vessels,e.g. such that the ethanol and cannabis plant material are slurried in afirst vessel of the centrifugal separator(s) 304 and the slurry is thentransferred to and centrifuged in a second vessel of the centrifugalseparator(s) 304.

One advantage of the present invention is that it permits the use ofcommercially available ethanol sources that may comprise a significantfraction of water. Particularly, the ethanol used in the system of thepresent invention, e.g. the alcohol present in the alcohol tank 301 andinjected by the alcohol pump 302 into the centrifugal separator(s) 304,may, in embodiments, comprise up to about 8% water; it may be possibleto use ethanol in which the water fraction is even higher. This featuregreatly reduces the cost, and greatly increases the availability, of theethanol solvent for use in the system.

Although not illustrated in FIG. 3, the cannabis plant material may, inembodiments, be subjected to various pre-processing steps before beingfed to the centrifugal separator(s) 304. By way of non-limiting example,such pre-processing steps may include at least one of acceptabilitytesting (e.g. for moisture content, contaminants, etc.) and sizereduction (e.g. by chopping, cutting, grinding, shredding, etc.).

It is to be expressly understood that, in embodiments (like thatillustrated in FIG. 3) in which two or more centrifugal separators 304are present, the centrifugal separators 304 may be arranged in series,in parallel, or in a combination thereof. For example, in the embodimentillustrated in FIG. 3, the first and second centrifugal separators 304a,b are arranged in series; the ethanol solvent and the raw cannabisplant material are first fed to a first centrifugal separator 304 a,where they are slurried and initially centrifuged, and the resultingliquor is then sent to a centrifugal separator 304 b, where it issubjected to further separation by centrifugation. The centrifugalseparation unit 300 may, but need not, comprise an impurity removalmeans, e.g. a filter, between successive centrifugal separators.Although not always necessary, in some embodiments in which centrifugalseparator(s) 304 are arranged at least partially in series, as in theembodiment illustrated in FIG. 3, later and/or downstream centrifugalseparator(s) may receive makeup ethanol from the ethanol tank 301 and/orthe refrigerator 303.

Regardless of the number and arrangement of the centrifugal separator(s)304, the centrifugal separation unit 300 produces two materials: a solidresidue and a crude oil. The solid residue is generally “wet,” i.e.comprising at least some residual ethanol and/or water, and the crudeoil generally comprises compounds extracted from the cannabis plantmaterial (e.g. cannabinoids and/or terpenes), solvent, and in many casessome residual solids. The solid residue is discarded (although it may incertain applications and embodiments be retained and optionallysubjected to further processing), but the crude oil is then passed tothe filter unit 400 illustrated in FIG. 4. In some embodiments, at leasta portion of the solid residue and/or at least a portion of the crudeoil is recycled to one or more centrifugal separator(s) 304.

Referring now to FIG. 4, a filter unit 400 of a system for preparing apurified cannabis extract, according to embodiments of the presentinvention, comprises an optional pump 401 and a filter assembly 402. Thepump 401 may be operable to supply at least a portion of the crude oilfrom the centrifugal separation unit 300 to the filter assembly at adesired pressure. The filter assembly 402 comprises a filter of anysuitable type (e.g. hot filtration, cold filtration, vacuum filtration,etc.), any suitable filter medium (whether a surface filter, a depthfilter, or both), and any suitable effective pore size. Upon passingthrough the filter assembly 402, whether directly from the centrifugalseparation unit 300 or via the pump 401 (or both), the filtered crudeoil is then passed to the concentration unit 500 illustrated in FIG. 5,although in some embodiments, as illustrated in FIGS. 3 and 4, a portionof the crude oil may be recycled from the filter assembly 402 back tothe centrifugal separation unit 300.

Referring now to FIGS. 5 and 10, a concentration unit 500 of a systemfor preparing a purified cannabis extract, according to embodiments ofthe present invention, comprises a concentration evaporator 501, acooler assembly 502, a vacuum pump 503, and a centrifugal pump 504. Thefiltered crude oil passes from the filter assembly 402 illustrated inFIG. 4 into the concentration evaporator 501, where it is heated toselectively evaporate the ethanol from the crude oil while leaving thecompounds extracted from the cannabis plant material (e.g. cannabinoidsand terpenes) in the liquid phase as a concentrated oil. In some, but byno means all, embodiments, the heating may be carried out under aboutatmospheric pressure. In some, but by no means all, embodiments, theheating may be to a temperature of between about 80 and about 90° C., orbetween about 90 and about 95° C. In some, but by no means all,embodiments, the heating may be carried out over a period of betweenabout 10 and about 15 minutes, or between about 20 and about 25 minutes.In some, but by no means all, embodiments, the heating may be carriedout in the presence of a catalyst. The concentration evaporator 501 maybe any suitable type of evaporator, including but not limited to acirculation evaporator, a falling film evaporator, a rising filmevaporator, a climbing and falling film plate evaporator, amultiple-effect evaporator, and/or an agitated thin film evaporator.

As illustrated, the concentrated oil is sent from the concentrationevaporator 501 to the static separation unit 700 illustrated in FIG. 7.The evaporated ethanol, which generally contains at least someimpurities (e.g. water), is then condensed in the cooler assembly 502,which is maintained at sub-atmospheric pressure, and in some embodimentsvacuum or near vacuum, by the vacuum pump 503. Upon collecting in abottoms tank of the cooler assembly 502, the condensed ethanol may bepumped via centrifugal pump 504 to any one or more of the centrifugalseparation unit 300 (e.g. to be immediately reused as part of theethanol solvent for extraction of the desired compounds from thecannabis plant material), the filter unit 400 (e.g. to aid in filtrationof the crude oil), to an ethanol storage tank that may be the same as ordifferent from the alcohol tank 301 (e.g. if the ethanol is sufficientlypure after condensation to be stored for reuse), and the rectificationunit 600 illustrated in FIG. 6 (e.g. to be further purified for use orreuse). Most typically, the ethanol collected in the cooler assembly 502requires further purification and most or all of the ethanol istherefore passed to the rectification unit 600.

Referring now to FIG. 6, a rectification unit 600 of a system forpreparing a purified cannabis extract, according to embodiments of thepresent invention, comprises a vacuum pump 601, optionally at least onestorage tank 602 (in this case two storage tanks 602 a,b), arectification heater 603, a rectification column 604, and a cooler 605.The vacuum pump maintains at least one of the rectification heater 603,the rectification column 604, and the cooler 605 at sub-atmosphericpressure, and in some embodiments vacuum or near vacuum. Therectification heater 603 receives the impure ethanol condensed in theconcentration unit 500 and heats the impure ethanol to cause theimpurities to be separated in the rectification column 604; theimpurities are collected in a bottoms and either discarded or furtherremediated in additional process units (not illustrated). In some, butby no means all, embodiments, the heating may be carried out under aboutatmospheric pressure. In some, but by no means all, embodiments, theheating may be to a temperature of between about 80 and about 90° C., orbetween about 90 and about 95° C. In some, but by no means all,embodiments, the heating may be carried out over a period of betweenabout 10 and about 15 minutes, or between about 20 and about 25 minutes.In some, but by no means all, embodiments, the heating may be carriedout in the presence of a catalyst.

Upon rectification, the now substantially pure ethanol is cooled in thecooler 605, optionally stored in one or more storage tanks 602, andrecycled; generally, the rectified ethanol is recycled to thecentrifugal separation unit 300, and particularly to the alcohol tank301, to be reused as part of the ethanol extraction solvent, but mayalso be recycled to other process units, such as the filter unit 400and/or the concentration unit 500.

Referring now to FIG. 7, a static separation unit 700 of a system forpreparing a purified cannabis extract, according to embodiments of thepresent invention, comprises one or more settling tanks 701, in thiscase two settling tanks 701 a,b. Generally, the settling tank(s) 701receive crude oil from the concentration unit 500 via an inlet disposedat or near a top of the settling tank(s) 701, and the crude oil thenremains in the settling tank(s) 701 for sufficient time to allowparticulate impurities, which in embodiments may include plant debris,proteins, lipids, etc., to precipitate out of the crude oil. While thesettling tank(s) 701 are depicted in FIG. 7 as conical settling tanks,it is to be expressly understood that any suitable settling device, suchas an inclined plate settler or other device, may be used as a settlingtank 701. After a predetermined residence time in the settling tank(s)701, a sediment comprising the solid particulate impurities has formedand is removed and discarded, while the settled crude oil is passed tothe decarboxylation and degassing unit 800 illustrated in FIG. 8.

In some (but by no means all) embodiments, static separation of thecrude oil received from the concentration unit 500 may be aided by anyone or more suitable means in the static separation unit 700 in additionto settling tank(s) 701. By way of first non-limiting example, the crudeoil may be contacted with a solid separating agent and/or a liquidseparating agent; in embodiments, a liquid separating agent may be aliquid (e.g. aqueous) solution or dispersion of a solid separating agent(e.g. a copper salt, a calcium salt, a sodium salt, a magnesium salt,silica, etc.). By way of second non-limiting example, the crude oil maybe centrifuged. By way of third non-limiting example, the crude oil maybe filtered.

Referring now to FIG. 8, a decarboxylation and degassing unit 800 of asystem for preparing a purified cannabis extract, according toembodiments of the present invention, comprises an atmosphere heatingsubunit 810 and a vacuum heating subunit 820. The atmosphere heatingsubunit 810 comprises an atmosphere heating vessel 811, which mayoptionally comprise an agitator, impeller, mixing paddle, or the like.The vacuum heating subunit 820 comprises a vacuum heating vessel 821,which may optionally comprise an agitator, impeller, mixing paddle, orthe like, and a vacuum pump 822. The atmosphere heating vessel 811receives the settled crude oil from the static separation unit 700 andheats the settled crude oil under approximately ambient or atmosphericpressure; this heating steps decarboxylates cannabinoids in the crudeoil, which are often present in larger quantities in their carboxylated,i.e. carboxylic acid, forms (which are generally biologically inactive)than in their biologically active free or neutral forms. The heating ofthe crude oil in the atmosphere heating vessel 811 may, in someembodiments, also accomplish various “winterization” processes (i.e.removal of unwanted compounds) and may cause gases dissolved in the oilto be removed. In some, but by no means all, embodiments, the heating inthe atmosphere heating vessel 811 may be carried out under aboutatmospheric pressure. In some, but by no means all, embodiments, theheating in the atmosphere heating vessel 811 may be to a temperature ofbetween about 80 and about 90° C., or between about 90 and about 95° C.In some, but by no means all, embodiments, the heating in the atmosphereheating vessel 811 may be carried out over a period of between about 10and about 15 minutes, or between about 20 and about 25 minutes. In some,but by no means all, embodiments, the heating in the atmosphere heatingvessel 811 may take place in the presence of a catalyst.

Once decarboxylation is substantially complete, the vacuum heatingvessel 821, which is maintained at a sub-atmospheric pressure (and insome embodiments vacuum or near-vacuum) by the vacuum pump 822, receivesthe decarboxylated oil from the atmosphere heating vessel 821 via aconduit. In the vacuum heating vessel 821, the decarboxylated oil isfurther heated under sub-atmospheric pressure as a preheating stepbefore entering the short-path distillation unit 900 illustrated in FIG.9; this preheating may, in some embodiments, assist in driving off gasesdissolved in the oil.

In some embodiments, the decarboxylation and degassing unit 800 may beeffective to convert substantially all of the carboxylated/carboxylicacid form of the compound of interest to the corresponding free orneutral form. By way of non-limiting example, the decarboxylation anddegassing unit 800 may be effective to convert substantially all of thecannabidiolic acid present in the settled crude oil to cannabidiol.

Referring now to FIG. 9, a short-path distillation unit 900 of a systemfor preparing a purified cannabis extract, according to embodiments ofthe present invention, comprises at least one short-path distillationapparatus 901, and in this embodiment two short path distillationapparatuses 901 a,b. As known and described in the art, a short-pathdistillation apparatus is an apparatus in which the distillate travels ashort distance, usually at sub-atmospheric pressure. Although notillustrated in detail in FIG. 9, each short-path distillation apparatus901 comprises a still pot (in which the oil exiting the decarboxylationand degassing unit 800 is received), a vertical condenser (known as a“cold finger,” and generally bent to direct the condensate), a coolingwater flow path, a vacuum or gas inlet, and a distillate vessel in whichthe final product is collected. The advantages of short-pathdistillation are numerous, among which are that the distillation iscarried out at lower temperature (thus decreasing the likelihood ofoxidation or other degradation of temperature-sensitive constituents)and that equipment losses are smaller due to the shortened distances andsmaller physical footprint of the distillation apparatus itself. It isto be expressly understood that, in embodiments in which the short-pathdistillation unit 900 comprises more than one short-path distillationapparatus 901, the short-path distillation apparatuses 901 may bedisposed in series, in parallel (as in FIG. 9), or in any combinedseries/parallel arrangement.

As illustrated in FIG. 9, the short-path distillation unit 900 mayoptionally comprise a vacuum heater 902, which may be the same as ordifferent from the vacuum heating vessel 821 of the decarboxylation anddegassing unit 800. The vacuum heater 902 of the short-path distillationunit 900 heats the oil under sub-atmospheric (in some embodiments,vacuum or near-vacuum) pressures, which may serve any one or more ofseveral purposes, including but not limited to further degassing of theoil and/or pre-treatment or pre-heating of the oil prior to entering theone or more short-path distillation apparatuses 901.

The finished product of the system described herein, obtained from theshort-path distillation unit 900, is a yellow-colored or goldencannabinoid and/or terpene oil of high purity and quality. Inembodiments, cannabinoids may make up at least about 70 wt %, andpreferably at least about 80 wt %, of the end product. In someembodiments, cannabidiol may make up at least about 70 wt %, andpreferably at least about 80 wt %, of the end product.

Referring now to FIG. 10, a method 1000 for preparing a purifiedcannabis extract is illustrated, according to embodiments of the presentinvention. In the embodiment illustrated in FIG. 10, the method 1000comprises a contacting step 1010, a centrifugation step 1020, afiltration step 1030, a concentration step 1040, a settling step 1050, adecarboxylation step 1060, a vacuum heating step 1070, and a distillingstep 1080.

In the contacting step 1010 of the method 1000, cannabis plant materialis subjected to a solvent extraction process, particularly an ethanolextraction process, by being contacted with a liquid solvent (e.g. amixture of ethanol and water). As a result of contacting step 1010, araw extract or slurry is produced; the raw extract typically comprisesthe solvent, a compound or compounds of interest (e.g. cannabinoidsand/or terpenes, including but not limited to cannabidiol), and proteinsand/or lipids soluble in the solvent or a component thereof.

In the centrifugation step 1020 of the method 1000, the raw extract orslurry is centrifuged to produce a solid residue and a crude oil. Thecrude oil, comprising at least most of the solvent and compound orcompounds of interest, is generally free of very large pieces of solidcannabis plant material, but may still contain smaller pieces.

In the filtration step 1030 of the method 1000, the crude oil isfiltered by any suitable means to produce a filtered crude oil. At thispoint, the filtered crude oil is generally free of macroscopic plantmatter, but may still contain dissolved or suspended solids, e.g.,proteins and lipids.

In the concentration step 1040 of the method 1000, the solvent or aportion thereof (i.e. ethanol) is removed from the crude oil andoptionally recycled to contacting step 1010 or another process step.Concentration step 1040 is generally accomplished by heating thefiltered crude oil to selectively evaporate the ethanol solvent, whichmay then be condensed for recycle or removal. Removal and recovery of atleast a portion of the solvent generally improves the efficiency ofsubsequent processing steps and results in a purer finished extract.

In the settling step 1050 of the method 1000, a sediment of solidparticles is precipitated from the concentrated crude oil by anysuitable means, although settling step 1050 generally comprises allowingthe crude oil to reside for a predetermined period in a settling vessel,such as a conical settling tank or inclined plate settler. Inembodiments, the settling of the sediment may be aided by any one ormore of the addition of a chemical (solid or liquid) separating agent,centrifugation, filtration, and so on. Generally, a first phaseresulting from settling step 1050 is a cannabinoid- and/or terpene-richphase (e.g. comprising at least most, and in embodiments at least 75%,of cannabinoids and/or terpenes in the concentrated crude oil, andhaving a low proportion of proteins and/or lipids), and the second phaseresulting from settling step 1050 is an impurity-rich phase (e.g.comprising at least most of the impurities in the concentrated crude oiland having a low proportion of substances of interest such ascannabinoids and/or terpenes); in embodiments, the impurities mayinclude proteins and/or lipids. Typically, the first and second phasesmay be substantially immiscible to facilitate further processing.

In the decarboxylation step 1060 of the method 1000, the cannabinoid-and/or terpene-rich phase formed in settling step 1050 is decarboxylatedby heating at approximately atmospheric or ambient temperature to form a“winterized” cannabinoid and/or terpene oil. The cannabinoid- and/orterpene-rich phase may, but need not, be agitated or stirred duringdecarboxylation step 1060.

In the vacuum heating step 1070 of the method 1000, the “winterized”cannabinoid and/or terpene oil is heated at sub-atmospheric (in someembodiments, vacuum or near-vacuum) pressures to further degas, purify,and/or pre-treat the oil and thereby form a distillation-ready oil. Insome embodiments, the vacuum heating step 1070 may comprise more thanone vacuum heating sub-step (e.g. by varying a temperature or pressure),in a single vessel or in two or more separate vessels.

In short-path distillation step 1080, the distillation-ready oil isdistilled at least once in at least one short-path distillationapparatus to produce a finished cannabinoid and/or terpene oil. Thefinished product of the method 1000 is a yellow-colored or goldencannabinoid and/or terpene oil of high purity and quality. Inembodiments, cannabinoids may make up at least about 70 wt %, andpreferably at least about 80 wt %, of the end product. In someembodiments, cannabidiol may make up at least about 70 wt %, andpreferably at least about 80 wt %, of the end product.

The method 1000 may optionally include any one or more additional stepsnot illustrated in FIG. 2. By way of non-limiting example, the solventremoved from the crude oil in concentration step 1040 may be rectifiedor otherwise purified and recovered.

Embodiments of the present invention may suitably be used to extract anyone or more cannabinoids from cannabis or other plant material.Cannabinoids amenable to extraction by embodiments of the presentinvention include, but are not limited to, cannabichromene-type (CBC)cannabinoids, e.g. (±)-cannabichromene (CBC-C₅), (±)-cannabichromenicacid A (CBCA-C₅ A), (±)-cannabichromevarin (CBCV-C₃), and(±)-cannabichromevarinic acid A (CBCVA-C₃ A); cannabichromanone-type(CBCN) cannabinoids, e.g. cannabichromanone (CBCN-C₅),cannabichromanone-C₃ (CBCN-C₃), and cannabicoumaronone (CBCON-C₅);cannabidiol-type (CBD) cannabinoids, e.g. (−)-cannabidiol (CBD-C₅),cannabidiol monomethyl ether (CBDM-C₅), cannabidiol-C₄ (CBD-C₄),(−)-cannabidivarin (CBDV-C₃), cannabidiorcol (CBD-C₁), cannabidiolicacid (CBDA-C₅), and cannabidivarinic acid (CBDVA-C₃); cannabielsoin-type(CBE) cannabinoids, e.g. (5aS,6S,9R,9aR)-cannabielsoin (CBE-C₅),(5aS,6S,9R,9aR)-C₃-cannabielsoin (CBE-C₃), (5aS,6S,9R,9aR)-cannabielsoicacid A (CBEA-C₅ A), (5aS,6S,9R,9aR)-cannabielsoic acid B (CBEA-C₅ B),(5aS,6S,9R,9aR)-C₃-cannabielsoic acid B (CBEA-C₃ B), cannabiglendol-C₃(OH-iso-HHCV-C₃), dehydrocannabifuran (DCBF-C₅), and cannabifuran(CBF-C₅); cannabigerol-type (CBG) cannabinoids, e.g. cannabigerol((E)-CBG-C₅), cannabigerol monomethyl ether ((E)-CBGM-C₅ A),cannabinerolic acid A ((Z)-CBGA-C₅ A), cannabigerovarin ((E)-CBGV-C₃),cannabigerolic acid A ((E)-CBGA-C₅ A), cannabigerolic acid A monomethylether ((E)-CBGAM-C₅ A), and cannabigerovarinic acid A ((E)-CBGVA-C₃ A);cannabicyclol-type (CBL) cannabinoids, e.g.(±)-(1aS,3aR,8bR,8cR)-cannabicyclol (CBL-C₅),(±)-(1aS,3aR,8bR,8cR)-cannabicyclolic acid A (CBLA-C₅ A), and(±)-(1aS,3aR,8bR,8cR)-cannabicyclovarin (CBLV-C₃); cannabinol-type (CBN)cannabinoids, e.g. cannabinol (CBN-C₅), cannabinol-C₄ (CBN-C₄),cannabivarin (CBN-C₃), cannabinol-C₂ (CBN-C₂), cannabiorcol (CBN-C₁),cannabinolic acid A (CBNA-C₅ A), and cannabinol methyl ether (CBNM-C₅);cannabinodiol-type (CBND) cannabinoids, e.g. cannabinodiol (CBND-C₅) andcannabinodivarin (CBND-C₃); cannabicitran-type or cannabitriol-type(CBT) cannabinoids, e.g. cannabicitran (CBT-C₅),(−)-(9R,10R)-trans-cannabitriol ((−)-trans-CBT-C₅),(+)-(9S,10S)-cannabitriol ((+)-trans-CBT-C₅),(±)-(9R,10S/9S,10R)-cannabitriol ((±)-cis-CBT-C₅),(−)-(9R,10R)-trans-10-O-ethyl cannabitriol ((−)-trans-CBT-OEt-C₅),(±)-(9R,10R/9S,10S)-cannabitriol-C₃ ((±)-trans-CBT-C₃),8,9-dihydroxy-Δ^(6a(10a))-tetrahydrocannabinol (8,9-Di-OH-CBT-C₅),cannabidiolic acid A cannabitriol ester (CBDA-C₅ 9-OH-CBT-C₅ ester),cannabiripsol (cannabiripsol-C₅),(−)-6a,7,10a-trihydroxy-Δ⁹-tetrahydrocannabinol ((−)-cannabitetrol), and10-oxo-Δ^(6a(10a))-tetrahydrocannabinol (OTHC); isocannabinoids, e.g.(−)-Δ⁷-trans-(1R,3R,6r)-isotetrahydrocannabinol,(±)-Δ⁷-1,2-cis-(1R,3R,6S/1S,3S,6R)-isotetrahydrocannabivarin, and(−)-Δ⁷-trans-(1R,3R,6R)-isotetrahydrocannabivarin; andtetrahydrocannabinol-type (THC) cannabinoids, e.g.Δ⁹-tetrahydrocannabinol (Δ⁹-THC-C₅), Δ⁹-tetrahydrocannabinol-C₄(Δ⁹-THC-C₄), Δ⁹-tetrahydrocannabivarin (Δ⁹-THCV-C₃),Δ⁹-tetrahydrocannabiorcol (Δ⁹-THCO-C₁), Δ⁹-tetrahydrocannabinolic acid A(Δ⁹-THCA-C₅ A), Δ⁹-tetrahydrocannabinolic acid B (Δ⁹-THCA-C₅ B),Δ⁹-tetrahydrocannabinolic acid-C₄ A and/or B (Δ⁹-THCA-C₄ A and/or B),Δ⁹-tetrahydrocannabivarinic acid A (Δ⁹-THCVA-C₃ A),Δ⁹-tetrahydrocannabiorcolic acid A and/or B (Δ⁹-THCOA-C₁ A and/or B),(−)-Δ⁸-trans-(6aR,10aR)-Δ⁸-tetrahydrocannabinol (Δ⁸-THC-C₅),(−)-Δ⁸-trans-(6aR,10aR)-tetrahydrocannabinolic acid A (Δ⁸-THCA-C₅ A),and (−)-(6aS,10aR)-Δ⁹-tetrahydrocannabinol ((−)-cis-Δ⁹-THC-C₅).

Embodiments of the present invention may suitably be used to extract anyone or more terpenes and terpenoids from cannabis or other plantmaterial. Terpenes and terpenoids amenable to extraction by embodimentsof the present invention include, but are not limited to, endo-borneol;δ-carene; bornyl acetate; α-ylangene; α-copaene; aromadendrene;eremophilene; longifolene; β-guaiene; valencene; β-bisabolene;γ-cadinene; β-selinene; neophytadiene; ferruginol; aristolone; β-amyrin;oleanane; ketoursene; α-amyrin; iridoids; iridoid glycosides; steroids,e.g. campesterol, β-sitosterol, γ-sitosterol, stigmasterol, tocopherols,cholesterol, testosterone, cholecalciferol, and ecdysone;hemiterpenoids, e.g. isoprene, prenol, and isovaleric acid; acyclicmonoterpenes, e.g. ocimene and myrcenes; monocyclic monoterpenes, e.g.limonene, terpinene, phellandrene, and umbellulone; bicyclicmonoterpenes, e.g. pinene α, pinene β, camphene, thujene, sabinene, andcarene; acyclic monoterpenoids, e.g. linalool, citronellal, citral,citronellol, geraniol, and geranyl pyrophosphate; monocyclicmonoterpenoids, e.g. grapefruit mercaptan, menthol, p-cymene, thymol,perillyl alcohol, and carvacrol; bicyclic monoterpenoids, e.g. camphor,borneol, eucalyptol, halomon, and ascaridole; sesquiterpenoids, e.g.farnesyl pyrophosphate, artemisinin, and bisabolol; diterpenoids, e.g.geranylgeranyl pyrophosphate, gibberellin, retinol, retinal, phytol,taxol, forskolin, aphidicolin, and salvinorin A; sesterterpenoids, e.g.geranylfarnesol; non-steroidal triterpenoids, e.g. saponins, squalene,lanosterol, oleanolic acid, ursolic acid, betulinic acid, and moronicacid); sesquarterpenes and sesquarterpenoids, e.g. ferrugicadiol andtetraprenylcurcumene; carotenes, e.g. α-carotene, β-carotene,γ-carotene, δ-carotene, lycopene, neurosporene, phytofluene, andphytoene; xanthophylls, e.g. canthaxanthin, cryptoxanthin, zeaxanthin,astaxanthin, lutein, and rubixanthin; polyterpenoids; norisoprenoids,e.g. 3-oxo-α-ionol, 7,8-dihydroionone, and precursors thereto; andactivated isoprenes, e.g. isopentenyl pyrophosphate (IPP), dimethylallylpyrophosphate (DMAPP), and precursors thereto.

A number of variations and modifications of the disclosure can be used.It would be possible to provide for some features of the disclosurewithout providing others. Additionally and/or alternatively, it may bepossible to vary or modify the order and/or sequence of method steps orsystem processing units relative to the embodiments specificallydescribed herein. Such modifications and variations are expresslycontemplated to be within the scope of the present disclosure.

Ranges have been discussed and used within the forgoing description. Oneskilled in the art would understand that any sub-range within the statedrange would be suitable, as would any number or value within the broadrange, without deviating from the invention. Additionally, where themeaning of the term “about” as used herein would not otherwise beapparent to one of ordinary skill in the art, the term “about” should beinterpreted as meaning within plus or minus five percent of the statedvalue.

Although the present disclosure describes components and functionsimplemented in the aspects, embodiments, and/or configurations withreference to particular standards and protocols, the aspects,embodiments, and/or configurations are not limited to such standards andprotocols. Other similar standards and protocols not mentioned hereinare in existence and are considered to be included in the presentdisclosure. Moreover, the standards and protocols mentioned herein andother similar standards and protocols not mentioned herein areperiodically superseded by faster or more effective equivalents havingessentially the same functions. Such replacement standards and protocolshaving the same functions are considered equivalents included in thepresent disclosure.

The present disclosure, in various aspects, embodiments, and/orconfigurations, includes components, methods, processes, systems and/orapparatus substantially as depicted and described herein, includingvarious aspects, embodiments, configurations embodiments,subcombinations, and/or subsets thereof. Those of skill in the art willunderstand how to make and use the disclosed aspects, embodiments,and/or configurations after understanding the present disclosure. Thepresent disclosure, in various aspects, embodiments, and/orconfigurations, includes providing devices and processes in the absenceof items not depicted and/or described herein or in various aspects,embodiments, and/or configurations hereof, including in the absence ofsuch items as may have been used in previous devices or processes, e.g.,for improving performance, achieving ease and/or reducing cost ofimplementation.

The foregoing discussion has been presented for purposes of illustrationand description. The foregoing is not intended to limit the disclosureto the form or forms disclosed herein. In the foregoing DetailedDescription, for example, various features of the disclosure are groupedtogether in one or more aspects, embodiments, and/or configurations forthe purpose of streamlining the disclosure. The features of the aspects,embodiments, and/or configurations of the disclosure may be combined inalternate aspects, embodiments, and/or configurations other than thosediscussed above. This method of disclosure is not to be interpreted asreflecting an intention that the claims require more features than areexpressly recited in each claim. Rather, as the following claimsreflect, inventive aspects lie in less than all features of a singleforegoing disclosed aspect, embodiment, and/or configuration. Thus, thefollowing claims are hereby incorporated into this Detailed Description,with each claim standing on its own as a separate preferred embodimentof the disclosure.

Moreover, though the description has included description of one or moreaspects, embodiments, and/or configurations and certain variations andmodifications, other variations, combinations, and modifications arewithin the scope of the disclosure, e.g., as may be within the skill andknowledge of those in the art, after understanding the presentdisclosure. It is intended to obtain rights which include alternativeaspects, embodiments, and/or configurations to the extent permitted,including alternate, interchangeable and/or equivalent structures,functions, ranges or steps to those claimed, whether or not suchalternate, interchangeable and/or equivalent structures, functions,ranges or steps are disclosed herein, and without intending to publiclydedicate any patentable subject matter.

Any of the steps, functions, and operations discussed herein can beperformed continuously and automatically.

The invention claimed is:
 1. A system for preparing a purified plantextract, comprising: a centrifugal separation unit, comprising at leastone centrifugal separator, configured to receive solid plant materialfrom a solid plant material source and a liquid solvent comprisingethanol from a separate solvent source, mix the solid plant material andthe liquid solvent in the at least one centrifugal separator to form aslurry, and centrifuge the slurry in the at least one centrifugalseparator to separate the slurry into a solid plant material residue anda raw extract, wherein the raw extract comprises at least one compoundof interest and at least most of the liquid solvent; a filtration unit,comprising a filter assembly, configured to filter the raw extract toremove entrained solid plant material from the raw extract; aconcentration unit, comprising an evaporator configured to receive theraw extract and heat the raw extract to remove at least most of thesolvent therefrom by evaporation to thereby form a concentrated extract;a settling unit, comprising at least one settling vessel, configured toreceive the concentrated extract and cause sedimentation of at least oneimpurity therefrom; a decarboxylation and degassing unit, comprising anatmosphere heating vessel and a vacuum heating vessel, wherein theatmosphere heating vessel is configured to receive the concentratedextract from the settling unit and heat the concentrated extract underapproximately ambient or atmospheric pressure to decarboxylate at leasta portion of the concentrated oil to form a decarboxylated oil, whereinthe vacuum heating vessel is configured to directly receive thedecarboxylated oil from the atmosphere heating vessel and heat thedecarboxylated oil under sub-atmospheric pressure to form a winterizedoil; and a short-path distillation unit, comprising at least oneshort-path distillation apparatus configured to receive the winterizedoil from the decarboxylation and degassing unit and distill thewinterized oil to form the purified plant extract.
 2. The system ofclaim 1, wherein the solid plant material is a raw cannabis plantmaterial.
 3. The system of claim 1, wherein the at least one compound ofinterest comprises at least one cannabinoid or terpene.
 4. The system ofclaim 3, wherein the at least one compound of interest comprisescannabidiol.
 5. The system of claim 1, wherein a content of the at leastone compound of interest in the purified plant extract is at least about70% by weight.
 6. The system of claim 1, wherein the liquid solventconsists essentially of (i) between about 92 and about 95 wt % ethanoland (ii) water.
 7. The system of claim 1, wherein the at least oneimpurity comprises at least one protein or lipid.
 8. The system of claim1, further comprising a rectification unit, configured to receiveevaporated solvent from the concentration unit and recover the solventfor recycle to at least one other unit of the system.
 9. A method forpreparing a purified plant extract, comprising: (a) mixing, within atleast one centrifugal separation unit, solid plant material receivedfrom a solid plant material source with a liquid solvent containingethanol received from a separate solvent source to form a slurry; (b)centrifuging, within the at least one centrifugal separation unit, theslurry to form a raw extract comprising at least one compound ofinterest and at least most of the liquid solvent; (c) filtering the rawextract to remove entrained solid plant material from the raw extract;(d) concentrating the raw extract by heating the raw extract to removeat least most of the solvent therefrom by evaporation to thereby form aconcentrated extract; (e) precipitating a sediment comprising at leastone impurity from the concentrated extract; (f) decarboxylating theconcentrated extract by heating the concentrated extract underapproximately ambient or atmospheric pressure in a first vessel to forma decarboxylated oil; (g) heating the decarboxylated oil undersub-atmospheric pressure in a second, vacuumized vessel directlyconnected to the first vessel to form a winterized oil; and (h)distilling the winterized oil by short-path distillation to form thepurified plant extract.
 10. The method of claim 9, wherein the solidplant material is a cannabis plant material.
 11. The method of claim 9,wherein the at least one compound of interest comprises at least onecannabinoid or terpene.
 12. The method of claim 11, wherein the at leastone compound of interest comprises cannabidiol.
 13. The method of claim9, wherein a content of the at least one compound of interest in thepurified plant extract is at least about 70% by weight.
 14. The methodof claim 9, wherein the liquid solvent consists essentially of (i)between about 92 and about 95 wt % ethanol and (ii) water.
 15. Themethod of claim 9, wherein the at least one impurity comprises at leastone protein or lipid.
 16. The method of claim 9, further comprisingrectifying the solvent evaporated in step (d) for recycle to at leastone of steps (a), (b), and (c).
 17. The method of claim 9, wherein acomposition is produced from the purified plant extract which comprisesat least about 70 wt % cannabinoids and terpenes and being substantiallyfree of proteins and lipids.
 18. The method of claim 17, wherein theproduced composition comprises at least about 70 wt % cannabidiol. 19.The method of claim 18, wherein the produced composition issubstantially free of cannabidiolic acid.